On skylake some of the registers are only writable when the correct power wells are enabled. Because of this watermarks have to be updated before the crtc turns off, or you get unclaimed register read and write warnings. This patch needs to be modified slightly to apply to -fixes. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92181 Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Cc: Matt Roper <matthew.d.roper@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_display.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index db4995406277..5345ffcce51e 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -4753,7 +4753,7 @@ static void intel_post_plane_update(struct intel_crtc *crtc) crtc->wm.cxsr_allowed = true; - if (pipe_config->wm_changed) + if (pipe_config->wm_changed && pipe_config->base.active) intel_update_watermarks(&crtc->base); if (atomic->update_fbc) @@ -13362,6 +13362,9 @@ static int intel_atomic_commit(struct drm_device *dev, dev_priv->display.crtc_disable(crtc); intel_crtc->active = false; intel_disable_shared_dpll(intel_crtc); + + if (!crtc->state->active) + intel_update_watermarks(crtc); } } -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html